5 speed Transmission and 4WD switch Questions 1995 80 series 1HDT

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Hi all. I have a 1995 80 series with a 1HDT engine, and a 5 speed transmission.

The transfer case 4WD is actuated by an electronic push button on the dash.

Overall the vehicle is in excellent condition and I am very happy with it. Have not had occasion to use it in 4WD much, but that will be coming soon as the rainy season hits here in Costa Rica.

I have a few questions.

1. For those of you with push button 4WD and locking hubs, is there any sort of light in your 4WD button? I ask because the only way I can tell is mine is in 4WD or not is by looking to see if the button is pressed in or not. If you see photos, I wonder if there was original a small light as there is on the defrost button. As can be seen previous owner put a sticker "H4" over the button, incidentally L4 does not engage either if button not depressed.

2. Would my transmission be an H151F?

(I have searched through the posts here, but there are so many 80 series, H151F vs H150 etc posts, I can not find anything clear and specific, even though I am sure it exists.)

3. Anybody with experience with the same transmission, is there a synchro between second and first to aid in downshifting or not? On my 80 I have to be almost stopped, or going at what equates to idle speed on the speedometer to easily shift into 1st.

What I am considering.

I am thinking to buy a used transmission, have it rebuilt, swap i tinto mine, and then rebuild mine, and swap i back, then keep my newly rebuilt spare as a spare or to sell when somebody else needs one. A good friend of mine has a 1997 with same setup and may well need a manual transmission in the coming years. Just curious what transmission I likely have or need.

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There is a small light to indicate that the defroster is on. As for your transmission issue, could it be the clutch?

Curious why a push button start was retrofitted to a diesel.
 

ArmyFJ

Lookin’ for mud in all the wrong places.
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Yours looks like an early H150 or H151 based on the casting (see post 72 here).

There may be a better way to find out the transmission you have (150 vs 151) but what I did was calculate the gear ratio from known info on the tire diameter, 3rd member, and RPMs: (tire diameter in inches)*(RPM) / (MPH * 3rd Member Ratio * T case Ratio * 336) i.e. (36.3 inch)*(3000 RPM) / (15MPH)*(5.29)*(1)*336 = ~4.08 (first gear for H151)

First does have a synchro ring.
 
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Joined
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There is a small light to indicate that the defroster is on. As for your transmission issue, could it be the clutch?

Curious why a push button start was retrofitted to a diesel.
Hi, thanks for the response. I do not think it is the clutch as there is no issue in any other gear. Assuming there is a synchro for shifting for 2nd to 1st, it is likely that.

As for the push button start it was installed by the previous owner who built this truck. Only thing I have done is ad a rear bumper and roof rack. Chasing a mechanical winch to go with the t-case winch takeoff, and shaft install,d but never got around to finding a winch. The push button start is designed for a four runner, or Hilux diesel. Works well.
 
Joined
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Messages
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Yours looks like an early H150 or H151 based on the casting (see post 72 here).

There may be a better way to find out the transmission you have (150 vs 151) but what I did was calculate the gear ratio from known info on the tire diameter, 3rd member, and RPMs: (tire diameter in inches)*(RPM) / (MPH * 3rd Member Ratio * T case Ratio * 336) i.e. (36.3 inch)*(3000 RPM) / (15MPH)*(5.29)*(1)*336 = ~4.08 (first gear for H151)

First does have a synchro ring.
Thanks, I had taken a look at that page before posting this, but since it was for a 70, I was looking for something a little more definitive. I guess splines and ration are my biggest concern.
 
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Hi, thanks for the response. I do not think it is the clutch as there is no issue in any other gear. Assuming there is a synchro for shifting for 2nd to 1st, it is likely that.

As for the push button start it was installed by the previous owner who built this truck. Only thing I have done is ad a rear bumper and roof rack. Chasing a mechanical winch to go with the t-case winch takeoff, and shaft install,d but never got around to finding a winch. The push button start is designed for a four runner, or Hilux diesel. Works well.
Sigh...just wish the USA would appreciate diesels more- nice work GM. I drive my HDJ-80 more than the FJ. Of course, being a manual helps too.
 
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Due to the dash buttons, your is a 1994 or earlier (mine is a 1995 and has a different button) there IS a light in the cluster that indicates 4WD is active, remember that once you are out of the 4X4 place, you will need to move the car backwards (or in a different direction it was going) for 1 m to dissengage the 4WD...to be honest, you can drive with locking hubs in the lock position and keep the button off until you need it, that way you dont have to get your feet dirty, I have had mine like so for about 6 years now, no issues...for the transmission part,there are synchros, you may have worn it out...best way to shift ANY manual is to depress clutch, shift into 2nd and then 1st that way you dont damage synchros...for reverse, depress clutch, 2nd, 1st then reverse...as for it being 151 or 150, well, have you seen the plaque? should be on driver's side right above booster, should look like mine, only mine says A442F, yours should say H151F or H150F or even R151F I doubt that last one as it is only for HZ engines and gasoline engines

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bottombracket

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Agree with all of the above.

I have a 1995 HDJ80 with an h150 conversion. It has an electrically actuated part time transfer case just like yours. Post a picture of the rear end of the transfer case.

You should have an H151 transmission. Post up your data plate so we can tell for sure.

One more thing, you may want to try Redline MT90 gear oil before rebuilding your transmission. My h150 is a little notchy in first and second gear when it is cold, I’m going to try the MT90 trick before swapping transmissions myself.
 
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Due to the dash buttons, your is a 1994 or earlier (mine is a 1995 and has a different button) there IS a light in the cluster that indicates 4WD is active, remember that once you are out of the 4X4 place, you will need to move the car backwards (or in a different direction it was going) for 1 m to dissengage the 4WD...to be honest, you can drive with locking hubs in the lock position and keep the button off until you need it, that way you dont have to get your feet dirty, I have had mine like so for about 6 years now, no issues...for the transmission part,there are synchros, you may have worn it out...best way to shift ANY manual is to depress clutch, shift into 2nd and then 1st that way you dont damage synchros...for reverse, depress clutch, 2nd, 1st then reverse...as for it being 151 or 150, well, have you seen the plaque? should be on driver's side right above booster, should look like mine, only mine says A442F, yours should say H151F or H150F or even R151F I doubt that last one as it is only for HZ engines and gasoline engines

View attachment 2303953
H151F is correct.

Are you suggesting when downshifting to make sure I go from third to second before going to first? Or if in second, shift it out of 2nd, back into second and then into 1st?

I find double clutching seems to work ok, but really need to get the speed right.

I have only had the truck a few months, and am still getting the hang of it. Have not had to do any work on it, just trying to get the hang of it. Will be swapping over to smaller mud tires soon. Going to 285/75R16 from 315/75R17.

I find double clutching deems to work ok, but really need to get the speed right.

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Go here to "see" all things of your car

1990 - 1998 Toyota LAND CRUISER HDJ80 OEM Parts | General sales region, , 936869

Now, double clutch is done when it is wearing down...
It is NOT a gasoline engine, you should not ever try to down shift from 3rd to 1st...as it is a diesel has lots of engine braking
At this time and from where I am at, I can´t show you how to drive a manual car...but one thing you must keep in mind always...it is a diesel...and with it also remember that it is NOT ana american made diesel engine...you will understand it soon enough I hope
Now...from a stand stil. you need to move, then, press clutch pedal (do not release) the move gear to 2nd then to 1st, then release clutch...in my previous comment I was basically telling you how to properly drive a manual transmission for it to mostly never wear down the synchros...down shifting is another thing...
 
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Go here to "see" all things of your car

1990 - 1998 Toyota LAND CRUISER HDJ80 OEM Parts | General sales region, , 936869

Now, double clutch is done when it is wearing down...
It is NOT a gasoline engine, you should not ever try to down shift from 3rd to 1st...as it is a diesel has lots of engine braking
At this time and from where I am at, I can´t show you how to drive a manual car...but one thing you must keep in mind always...it is a diesel...and with it also remember that it is NOT ana american made diesel engine...you will understand it soon enough I hope
Now...from a stand stil. you need to move, then, press clutch pedal (do not release) the move gear to 2nd then to 1st, then release clutch...in my previous comment I was basically telling you how to properly drive a manual transmission for it to mostly never wear down the synchros...down shifting is another thing...
Thanks you.

I was just trying to understand your meaning to see if I was missing something. I have bene driving standards, and standard diesels since long before I was able to legally have a license, and am quite a competent driver by most people's standards, leaving my own opinion out of it.

Re-reading what you are saying, you mean when 80 is parked, in order to make it go into 1st gear more easily, shift into 2nd, and then into first, without first releasing clutch?

If that is what you were saying, I got it, and often do that, and similar for reverse.

My issue, is when I am driving, and need to downshift either approaching a hill, on a hill, or whatever, there seems to be no help from the synchro ring going from 2nd to 1st gear. Basically I slow down to the same speed the vehicle would be going in 1st gar at an idle, and then double clutch it into 1st. It seems to go a little easier with double clutch. There is no gear gnashing, it just won't go, until I get speed right. I will see if I can make a video, but hard to really capture I think. May just need a synchro ring since 2nd to 1st is common shift especially in train where thi truck ha lived. It is not a huge problem, but a little mores that it is currently sitting on 35" tires. Will be scaling back tire diameter form 34.6" to 32.8" Not a huge difference, but should give it back a little more low end grunt in second gear.

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Looks good
Now, as I said, japanese diesels are different than american...you will do it easier matching revs to speed and downs***...it takes a bit of time to get use to it, not much for you...
 
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Looks good
Now, as I said, japanese diesels are different than american...you will do it easier matching revs to speed and downs***...it takes a bit of time to get use to it, not much for you...
Thanks, yeah that is basically what I have been doing, but looking for a path forward to rebuild my current transmission or replace with an upgrade.

There was some talk of one for a 70 series pickup with lower 1st and 2nd gear ratios, but requires changing the input shaft.

Will start looking around to see who rebuilds and cost of parts and possibility to source a second box.
 
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My issue, is when I am driving, and need to downshift either approaching a hill, on a hill, or whatever, there seems to be no help from the synchro ring going from 2nd to 1st gear.
You'll find to down shift from second to first with the H151 behind a 1HD-T, you almost need to be at a slow walking speed.
Double declutching can help, and stab the throttle to bring the engine speed up 500rpm as you shift down into 1st

The H150, H151 gearboxes are known to have issues with synchro rings particularly in the early years

I highly recommend changing the gear oil to redline as mentioned earlier, or I like to use Castrol VMX-M (the last 'M' is important). It's the same grade as what Toyota specify, but a slightly lighter oil, and has anti friction additives in it. It's a cheap and simple exercise to change the oil, and it can make a huge difference. I find it takes a few 1000 miles for it to really take effect, and changing it again after 10-15k miles helps more.
 
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Bell housing and input shaft?
Just Bell Housing ...the H152F is from the newer diesel V8 turbo Toyota pick up truck, it will be strong enough
Now, you want something easier to find...then get a R151F from a smaller pick up truck (Hilux here maybe Tacoma there?) and then use the bigger clutch that Isuzu has and WILL fit the shaft...that is how we do it down here, has worked years and years like that...Also...if you like something a bit fancier, try to get the 6 speed from an FJ Cruiser and fit it...as always, keep the Bell Housing of the H151F
 
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